561556320 has 192 divisors, whose sum is σ = 1967099904. Its totient is φ = 133724160.

The previous prime is 561556297. The next prime is 561556321. The reversal of 561556320 is 23655165.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561556321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 191989 + ... + 194891.

It is an arithmetic number, because the mean of its divisors is an integer number (10245312).

Almost surely, 2^561556320 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 561556320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (983549952).

561556320 is an abundant number, since it is smaller than the sum of its proper divisors (1405543584).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

561556320 is a wasteful number, since it uses less digits than its factorization.

561556320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2965 (or 2957 counting only the distinct ones).

The product of its (nonzero) digits is 27000, while the sum is 33.

The square root of 561556320 is about 23697.1795790132. The cubic root of 561556320 is about 825.0199297298.

The spelling of 561556320 in words is "five hundred sixty-one million, five hundred fifty-six thousand, three hundred twenty".